Method and device for diagnosing in a motor vehicle a driver&#39;s fitness drive

ABSTRACT

A method is for diagnosing the driving capability of a driver of a motor vehicle, in which changes in driver condition are ascertained from physiological measured values derived from the driver while driving in the vehicle and evaluated, and if the changes are serious, a warning is issued or remedial actions are initiated, wherein the physiological measured values ascertained while driving in the vehicle are combined by a corresponding expert system with health-relevant data for the driver ascertained in stationary fashion, and with data indicating driver stress that are estimated in particular from the instantaneous traffic situation and instantaneous operating state of the vehicle, and the changes in the driver&#39;s condition are weighted with the estimated driver stress and interpreted. An apparatus for performing the method is characterized in that the expert system is implemented in an onboard computer of the vehicle which is connected via a bus internal to the vehicle to a mobile driver condition sensor suite that supplies the physiological measured values, to a memory/transfer medium that delivers the biographical data and/or the health-relevant data ascertained in stationary fashion, and to an ACC system and driving direction system internal to the vehicle.

FIELD OF THE INVENTION

The present invention relates to a method and apparatus for diagnosingthe driving capability of a driver in a motor vehicle, in which changesin driver condition are ascertained from physiological measured valuesderived from the driver while driving in the vehicle, and if the changesare serious, a warning is issued or remedial actions are initiated.

BACKGROUND INFORMATION

Conventional systems which appraise the driver's condition on the basisof physiological parameters measured in the vehicle include, forexample, interactive systems that request from the driver, whiledriving, certain input actions on the basis of which the drivingcapability of the driver is determined. Systems also exist which sensethe eyelid blink frequency via a video camera with downstream imageanalysis. From the acquired blink frequency, conclusions can in turn bedrawn regarding the driving capability of a driver in the motor vehicle.

Also available in the home context are systems, for example, exercisemachines equipped with ergometric functions, which allow conclusions asto the health of the user by way of physiological measured values suchas blood pressure, pulse rate, skin impedance, etc.

The informativeness of conventional systems or systems under developmentin terms of assessing the driving capability of the driver in a motorvehicle is considerably limited, however, by the fact that the onlymethods possible are those that do not use fixed electrodes or catheterson the driver's body, but instead must make do with contacts on bareskin areas or with entirely non-contact measurements, such as theaforesaid acquisition of the eyelid blink frequency a video camera.

SUMMARY

It is an object of the present invention to increase the reliability andinformativeness of a method for diagnosing the driving capability of adriver of a motor vehicle in order, as applicable, to output to thedriver a warning based on the diagnosis of driving capability and toinitiate remedial actions if necessary.

According to an example embodiment of the present invention, thephysiological measured values measured instantaneously while driving maybe combined with stationary health-relevant data for the driverascertained in the home context, and may be weighted and interpreted byan expert system with data, present in the vehicle or derived,indicating driver stress, in particular concerning the instantaneoustraffic situation and the instantaneous vehicle operating state orchanges in the driver's condition.

The data obtained in the vehicle from the vehicle operating state andfrom the instantaneous traffic situation may be used to derive anestimated value regarding the instantaneous driver stress, with whichthe instantaneous physiological data about the driver measured whiledriving in the vehicle, and the stationary health-relevant data obtainedin the home context and combined therewith, may then be weighted andinterpreted in a more informative fashion to yield a comprehensiveappraisal of the driver's driving capability.

Circulatory data such as the driver's pulse rate and blood pressure maybe particularly suitable for the acquisition of physiological values forthe driver in the vehicle. Such circulatory data may easily be obtainedwith conventional transducers, for example, in the form of a wristwatch,and transmitted wirelessly to a receiver in the vehicle.

Also suitable may be a measurement in the vehicle of the driver's skinimpedance. This physiological value may also be obtained usingconventional transducers attached to the driver's skin, and transmittedwirelessly to a receiver in the vehicle.

As described previously, a video camera with downstream image processingmay be used to measure an eyelid blink parameter, i.e., the driver'sblink frequency and speed, which may provide clear information aboutdriver fatigue.

An estimate of the instantaneous stress on the driver as a result of asituation in terms of driving, traffic, and the environment may be madefrom data that may be present in the vehicle or derivable. For example,data from a destination guidance system may be used. These may indicatethe static traffic situation in which the driver finds him- or herself,e.g., urban, rural, at a complex intersection, on a narrow mountainroad. Information regarding the dynamic traffic situation may beobtained from road condition data, weather data, and time of day; byusing the sensed speed of the particular vehicle, for exampleacceleration values and frequency; and from the speed of other vehicles,for example based on ACC (Adaptive Cruise Control) signals. An estimateof the instantaneous traffic density, based on ACC data and using futurevideo sensor apparatus, appears possible in principle.

In an example method according to the present invention, an estimatethat is made of the instantaneous driver stress may be combined, by theuse of an expert system, with the instantaneous physiological situationof the driver as supplied by the aforementioned physiological dataacquired with the use of a driver condition sensor suite. As a result ofthis association, it may be possible to determine how the stress due todriving is reflected in the physiological data. It may be assumed inthis context that other influences, for example, interaction withpassengers or in conversations by mobile telephone in traffic, may haveless of an influence on the driver's stress level. Stress resulting fromdriving may serve as an “ergometer” with which a patient, i.e., in thiscase, the driver, is brought into a known stress situation. Thedifference may also be that driving may represent more a mental andpsychological stress than a physical one. From the physiologicalreaction of the driver's body to this stress, conclusions may then bedrawn as the state of the driver's health. For example, extreme systolicblood-pressure values and rapid pulse rates may occur, and adetermination may be made as to whether they are correlated withdifficult traffic situations or are occurring without such stresses. Inthe latter case, the driver may be warned and may be advised to seekmedical help. Information as to excessive fatigue or drugs (such asblood alcohol level) may be obtained in a conventional fashion frommeasured values of the driver condition sensor suite operated in thevehicle. As a result of this weighting with the driver stress estimatedfrom the traffic situation and from the vehicle operating status, betterconclusions may be drawn as to the relevance of this information.

In an example method according to the present invention, as mentioned,the instantaneous physiological data obtained using the mobile drivercondition sensor suite in the vehicle may also be combined withhealth-relevant data for the driver ascertained on a stationary basis.Stationary health data of this kind may be ascertained, for example,using home-based systems that are capable of obtaining from the user's(in this case the driver's) biological material, such as urine, feces,sweat, etc., information about the person's state of health.Health-relevant data may also be collected and stored in home healthdevices, for example bicycle ergometers, exercise machines, blood-sugarmeasurement instruments, scales, etc.

These stationary data may be obtained in static situations or duringmuscle work, and not under predominantly mental/psychological stresssuch as may occur in a motor vehicle. The stationary data may be storedin a suitable storage/transfer medium, and the latter may be read by aninput arrangement in the vehicle or the stored information may be sentto a receiver in the vehicle. This memory/transfer medium may be, forexample, a chip card, a wristwatch with wireless transmissiontechnology, a mobile radio system, etc.

The expert system in the motor vehicle may weight the instantaneousphysiological data (obtained while driving using the mobile drivercondition sensor suite) with the driver's health-relevant data obtainedin stationary fashion, and thereby may obtain a more comprehensivepicture of the driver's state of health, so that in the event of seriousdeviations from normal values, remedial actions may be initiated asapplicable.

In the event no stationary measured values concerning the driver's stateof health in the home context may be obtained, standard values may beassumed by the diagnostic method according to the present invention, andthose standard values may be refined using inputted biographical datasuch as the driver's gender, age, and weight.

In an example embodiment, an expert system may be set up as a learningsystem. Initially, before a valid diagnosis as to driving capability isissued, a learning phase with at least one test drive by the driver maybe performed in the vehicle, including a variety of stress levels andtraffic situations.

An apparatus configured to perform the example method may contain theexpert system implemented in an onboard computer of the vehicle, and theonboard computer may be connected via a vehicle bus system to the drivercondition sensor suite which supplies the physiological measured values;to a memory/transfer arrangement that delivers the biographical dataand/or health-relevant data ascertained in stationary fashion; to anarrangement that estimates the driver stress based on the instantaneoustraffic situation and the instantaneous vehicle operating state andtransmits it to the onboard computer; and also an arrangement thatimparts to the driver as a warning signal, or that emits to theenvironment, a signal indicating an overload or a driver stress that isnot appropriate for the situation. An ACC system and a vehiclenavigation system may be used to ascertain the instantaneous trafficsituation and to appraise the driver stress. In order to identify thedriver, the onboard computer and the expert system residing therein maybe connected to a vehicle access authorization control unit.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic view of a system according to the presentinvention.

DETAILED DESCRIPTION

The description below describes, with reference to the functional blockdiagram illustrated in FIG. 1, steps of an example driver diagnosismethod according to the present invention, as well as functions of anexample embodiment of an apparatus configured to perform the method.

System 1, illustrated in FIG. 1 in the form of functional blocks,includes the following functional units:

-   -   an expert system 10 implemented in an onboard computer;    -   an ACC and navigation system 11 having associated sensors 2 a, 2        b and a radio antenna 2 c;    -   an arrangement 12 for acquiring the stationary (at-home)        physiological data of a driver;    -   arrangements 15, 18 for storing/transferring to the onboard        computer the health-relevant data obtained in stationary        fashion;    -   a vehicle bus system 3 for connecting various units in the        vehicle; and    -   a driver condition sensor suite 4 located in vehicle 5.

An optionally provided driver access authorization control unit is notillustrated.

Sensors 2 a, 2 b associated with ACC and navigation system 11, and radioantenna 2 c, serve to acquire environmental/traffic situation 20, forexample, via radar waves, video image acquisition, and/or ultrasonicwaves, and to receive driving direction information via GSM mobileradio. In ACC and navigation system 11, ACC information 20 acquired bythe corresponding sensors 2 a, 2 b and antenna 2 c—for example, thenumber, speed, and heading of other vehicles, and driving directioninformation; also the vehicle's own heading and speed, road category,urban/rural, weather data, road condition, topographic data, etc.—isascertained, and the driver stress is estimated therefrom andtransmitted in the form of a signal 14 to expert system 10 in theonboard computer. Expert system 10 also receives, from mobile drivercondition sensor suite 4 (which may include an electrocardiogram orelectrocardiograph), signals 17 that indicate the physiological data forthe driver in the vehicle acquired by driver condition sensor suite 4.The physiological data ascertained in stationary home-based system 12,as well as biographical data, are inputted via memory/transfer medium 15(i.e., a chip card), using an input/read medium 18, into expert system10. In the latter, the stationary health data thus inputted are combinedwith the instantaneous physiological data 17 for the driver acquired bymobile driver condition sensor suite 4 while driving, weighted withestimated value 14 for driver stress, and interpreted.

Expert system 10 weights the physiological and biographical data withthe estimated driver stress 14 and, if the changes in driver conditionare serious, generates a warning for the driver and/or a signal 13,e.g., emittable externally via GSM radio, which indicates the overloador situationally inappropriate stress on the driver so that remedialactions may be initiated. In one example embodiment, the onboardcomputer or expert system may be connected to a driver accessauthorization control unit which performs the identification of thedriver and delivers it to the expert system.

The core of the example method according to the present invention, andof the example embodiment of an apparatus according to the presentinvention configured to perform the example method, is thus thecombination, performed by the expert system, of physiological data 17(obtained while driving via driver condition sensor suite 4) with thestationary health-relevant data obtained in the home context anddelivered via memory/transfer medium 15, and the weighting of thesecombined data using an estimated value 14 that indicates driver stress,which is estimated as an independent variable based on the trafficsituation and driving direction information obtained from the onboardACC and navigation system 11 and is delivered to expert system 10. Fromthe weighted change in driver condition, expert system 10 decides ifthat change is so serious that driving capability is questionable, if awarning signal needs to be issued to the driver, or if applicableremedial actions need to be initiated.

In the example embodiment described above, expert system 10 resides inan onboard computer of a vehicle 5. The example method according to thepresent invention is not, however, limited to this example embodiment,but rather may also be usable if expert system 10 resides outsidevehicle 3 at a central location, to which the physiological dataascertained by way of the mobile driver condition sensor suite, thestationary physiological and biographical data, and the informationabout the traffic situation and the driving direction informationascertained from the ACC system and navigation system 11 are thenconveyed.

As described above, the present invention may be applied to ascertainthe driving capability of the driver of a motor vehicle. It maynevertheless be apparent to those skilled in this art that the presentinvention may also be applicable to operating capability diagnosis inthe context of drivers (or pilots) of other vehicles and a mode oftransportation, for example ships, aircraft, and rail vehicles. The term“motor vehicle” or “vehicle” used herein is thus to be construedbroadly.

1. A method for diagnosing a driving capability of a driver of a motorvehicle, comprising the steps of: ascertaining health-relevant data forthe driver obtained while the driver is stationary; acquiringphysiological measured values for the driver while driving in thevehicle; combining, by an expert system, the physiological measuredvalues with the health-relevant data; ascertaining changes in a drivercondition from the combined physiological measured values andhealth-relevant data; estimating a variable indicating a driver stressfrom data that is one of present and derived in the vehicle concerningan instantaneous traffic situation and an instantaneous vehicleoperating state; weighting and interpreting, by the expert system, thechanges in the driver condition with the variable indicating a driverstress in order to detect if the driver is in an impaired condition; andone of issuing a warning and initiating remedial actions to counteractthe driver condition if the weighted and interpreted changes in thedriver condition fulfill at least one predetermined criterion pertainingto the impaired condition.
 2. The method of claim 1, wherein thephysiological measured values include circulatory measured values. 3.The method of claim 2, wherein the circulatory measured values include apulse rate and a blood pressure of the driver in the vehicle.
 4. Themethod of claim 1, wherein the physiological measured values acquiringstep includes the substep of sensing an impedance of a skin of thedriver, the physiological measured values including the impedance. 5.The method of claim 1, wherein the physiological measured valuesacquiring step includes the substep of measuring an electrocardiogram ofthe driver, the physiological measured values including theelectrocardiogram .
 6. The method of claim 1, wherein the physiologicalmeasured values acquiring step includes the substep of sensing an eyelidblink frequency of the driver, the physiological measured valuesincluding the eyelid blink frequency.
 7. The method of claim 1, whereinthe health-relevant data include physiological data measured while thedriver is stationary and biographical data.
 8. The method of claim 7,wherein the physiological data include ergometric data measured on anergometric device.
 9. The method of claim 7, wherein the biographicaldata include at least one of an age, a weight, and a gender.
 10. Themethod of claim 7, wherein if the physiological data measured while thedriver is stationary are not present or are not measurable, thehealth-relevant data include standard values refined using inputtedbiographical data.
 11. The method of claim 10, wherein the inputtedbiographical data includes a gender, an age, and a weight.
 12. Themethod of claim 1, wherein the health-relevant data include bloodanalysis values of the driver.
 13. The method of claim 12, wherein theblood analysis values include a blood sugar level.
 14. The method ofclaim 1, further comprising the step of calculating the driver stressfrom a combination of the instantaneous traffic situation andinstantaneous operating state data for the motor vehicle, theinstantaneous traffic situation estimated from the number, speed, andheading of other vehicles and from relevant driving directioninformation for the vehicle, the instantaneous operating state dataincluding a heading and a speed of the vehicle.
 15. The method of claim1, further comprising the step of initially performing at least one testdrive by the driver during a learning phase before a valid diagnosis ofthe driving capability is issued, wherein a learning system is used asthe expert system, the test drive including a variety of stress levelsand traffic situations.
 16. An apparatus for diagnosing a drivingcapability of a driver of a motor vehicle, comprising: a vehicle-baseddriver condition sensor suite configured to supply physiologicalmeasured values; a memory/transfer arrangement configured to deliver atleast one of biographical and health-relevant data, the data ascertainedwhile the driver is stationary; a traffic/vehicle monitor arrangementconfigured to ascertain and transfer an instantaneous traffic situationand an instantaneous operating data of the motor vehicle to an onboardcomputer of the motor vehicle; a transmission arrangement configured totransfer a signal to an environment, the signal indicating a driverstress that is inappropriate for the instantaneous traffic situation; anexpert system arranged in the onboard computer; and a vehicle busarranged to connect the onboard computer to the vehicle-based drivercondition sensor suite, the memory/transfer arrangement, thetraffic/vehicle monitor arrangement, and the transmission arrangement.17. The apparatus according to claim 16, wherein the vehicle-baseddriver condition sensor suite includes a pulse and blood-pressure meter.18. The apparatus according to claim 16, wherein the vehicle-baseddriver condition sensor suite includes a skin impedance sensor.
 19. Theapparatus according to claim 16, wherein the vehicle-based drivercondition sensor suite includes an electrocardiograph.
 20. The apparatusaccording to claim 16, wherein the vehicle-based driver condition sensorsuite includes a video camera with a downstream image evaluation systemconfigured to sense and evaluate the driver's eyelid blink frequency.21. The apparatus according to claim 16, wherein the memory/transferarrangement includes a memory medium and an input/read apparatusconnected to the onboard computer and configured to read the memorymedium.
 22. The apparatus according to claim 21, wherein the memorymedium includes a chip card.
 23. The apparatus according to claim 16,wherein the traffic/vehicle monitor arrangement includes an ACC systemand a vehicle navigation system connected to corresponding sensors. 24.The apparatus according to claim 16, wherein the transmissionarrangement includes a radio transmission system.
 25. The apparatusaccording to claim 24, wherein the radio transmission system includes aGSM mobile data radio system.
 26. The apparatus according to claim 16,wherein the onboard computer is connected to an access control unit ofthe vehicle, the access control unit configured to perform anidentification of the driver.